Actually, the 5U4 rectifiers are Sovtek as are the 6922s. The 6sn7s are chinese. At least that's what was in mine. The 6sn7 were replaced by 1950's Raytheon's and the 6922's were swaped for some NOS Ediswain. These changes were suggested by Kevin Deal of Upscale Audio and they are a good return on the investment (approx. $200). You should give them a call.
